Achieving sanitation in the disposal of human waste has been of concern for centuries. Water-flushed latrines have been discovered which date back as far as 2500 B.C., and Rome is known to have had some sort of flush latrine system in the fourth century A.D. However, these devices typically consumed great quantities of fresh water to accomplish their task.
Despite the presence of these early systems, efficient human waste disposal was accomplished only fairly recently. It was not until the late 1800s that Britain invested in sewer systems. Even at that time, such systems relied on a constant supply of water to dilute and remove sewage. Water closets or toilets as we know them today were not developed until nearly the twentieth century, when cistern-type flush toilets became available in some areas. Since that time, numerous improvements have been made, resulting in the modern flush toilets which we now take for granted.
One early inventor of a flush toilet recommended that it be flushed perhaps once or twice each day. In contrast, today's germ-conscious society generally insists that a toilet be flushed after every use. Furthermore, an effort to reduce germs and odors, various water conditioners are frequently placed in toilets, such as disinfectants, deodorizers, and other chemicals or solutions. There are a number of devices for operation with flush toilets to dispense these conditioners into toilet water. The general purpose of these devices is to mix conditioner with the water which remains in the toilet bowl after flushing.
One of the primary disadvantages of prior art toilet conditioner devices relates to their need for frequent replacement. Many people consider the performance of any toilet-related maintenance to be extremely unpleasant. Thus, even though replacement of the prior art devices might be considered simple and convenient in any other context, it becomes an unpleasant task when associated with a toilet. This is particularly true of devices which are located within the toilet bowl itself. However, many people also dislike having to remove the cover of the toilet's flush tank to replace tank-positioned dispensers. Furthermore, some such dispensers are positioned on the bottom of the flush tank, requiring a person to reach to the bottom of the tank through a foot or more of water.
A related problem with prior art toilet conditioner devices is that they are not easily recyclable or reusable. Most such devices are disposable, resulting in a waste of plastic components, not to mention the associated cost of replacing such components. In addition, consumers are beginning to prefer goods which do not have harmful environmental effects such those produced by disposable plastic devices.
A further disadvantage of many prior art conditioner devices is that much of the dispensed chemical is wasted. This is particularly true of devices which are simply placed within a toilet's flush tank. Most of the water entering the flush tank is consumed during flushing, and does not remain in the toilet bowl after flushing. Thus, the most significant portion of any water conditioner dispensed in the flush tank is rapidly flushed down the toilet drain, providing little or no benefits. In addition, such wasted water conditioner may in some cases have a detrimental environmental impact. Generally, it is desirable to limit the amount of chemical water conditioner used to provide the desired deodorant, coloring, germicidal or other associated benefits.
It is furthermore desirable to limit or at least regulate the actual amount of conditioner dispersed during or between each flush in order to thereby limit replacement expenses and to reduce the sometimes harmful environmental effects associated with chemicals in waste waters. However, many prior art devices are unable to meter the amount of conditioner placed within the surrounding water. For instance, soluble bars will continue to dissolve while they are surrounded by water. Thus, the amount of dispersed conditioner for each flush is dependent on the time between flushes. Some liquid conditioner dispensers suffer from this same problem. Furthermore, the rate of conditioner dispersal is not constant in many devices, tending to either increase or decrease with the life of the devices. These shortcomings result in an inefficient use of water conditioner.
Some prior art dispensing devices disperse conditioner into the overflow pipe of a toilet flush tank. A toilet's overflow pipe communicates bowl makeup water directly to the toilet bowl to refill the toilet bowl after flushing. Accordingly, most of the water passing through the overflow pipe remains in the toilet bowl after flushing. Conditioner dispersed in the bowl makeup water likewise ends up in the toilet bowl rather than being swept primarily down the toilet drain with flush water.
One type of conditioner dispenser used in conjunction with a toilet overflow pipe utilizes a solid or granular conditioner. Water entering the toilet overflow pipe passes through or over the conditioner, thus dissolving a portion of the conditioner and carrying it into the toilet bowl. An example of this type of device is described in U.S. Pat. No. No. 2,697,841.
Some disadvantages of using a solid or granular conditioner are mentioned above. Another disadvantage is that dissolvable solid materials are much more difficult to formulate than liquid conditioners. Generally, dissolvable solid conditioners are more expensive than liquid conditioners. Furthermore, they are available in only a limited number of formulations as compared to liquid formulas.
The prior art devices which place granular or solid conditioners within an overflow pipe are also somewhat difficult to install, replace or refill. In addition, they often interfere with the free flow of water through the overflow pipe. If such interference is severe enough, it prevents complete filling of the toilet bowl.
Another type of conditioner dispersing device used with an overflow pipe dispenses liquid conditioner into the overflow pipe during every flush cycle. U.S. Pat. No. No. 2,761,151 shows this type of device. Devices for dispensing liquid conditioner into the toilet overflow pipe are often complex. Such devices typically include valves, springs, and other moving parts which are prone to failure or improper operation. The complexity of the devices also increases their cost. Such devices are furthermore difficult to install and replace, decreasing their usefulness to the typical person.
Because of the various inadequacies of the prior art, discussed above, many people simply choose not to use the prior art devices. The invention described below addresses the inadequacies of the prior art, providing a conditioner dispensing apparatus which is uniquely efficient, convenient, and inexpensive. The advantages of the invention are presented in more detail in the discussion which follows.